Note 8 - Fair Value Measurements (Details Textual)	3 Months Ended		12 Months Ended
	Mar. 31, 2022 USD ($)	Mar. 31, 2021 USD ($)	Dec. 31, 2021
Provision for Loan and Lease Losses	$ 175,000	$ 75,000
Number of Foreclosed Real Estate Properties	0
Impaired Loan [Member]
Provision for Loan and Lease Losses	$ (1,000)	9,000
Foreclosed Real Estate [Member]
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate, Write-down or Reserve, Amount	$ 0	$ 0
Fair Value, Inputs, Level 3 [Member] | Impaired Loan [Member]
Fair Value Inputs, Estimated Selling Costs			10.00%
Fair Value, Inputs, Level 3 [Member] | Impaired Loan [Member] | Minimum [Member]
Fair Value Inputs, Estimated Selling Costs	10.00%
Fair Value, Inputs, Level 3 [Member] | Impaired Loan [Member] | Maximum [Member]
Fair Value Inputs, Estimated Selling Costs	23.00%
Fair Value, Inputs, Level 3 [Member] | Impaired Loan [Member] | Weighted Average [Member]
Fair Value Inputs, Estimated Selling Costs	11.00%
Fair Value, Inputs, Level 3 [Member] | Foreclosed Real Estate [Member]
Fair Value Inputs, Estimated Selling Costs	65.00%